Vacuum processing device

ABSTRACT

A device of executing vacuum processing is provided with: a chamber including a single main chamber executing the vacuum processing and being capable of keeping the chamber as a whole in a depressurized state; a plurality of feeding rollers so arranged as to hang down a plurality of threads in the main chamber with keeping the threads from each other; a plurality of winding bobbins respectively winding the plurality of threads independently, the winding bobbins arranged in the chamber horizontally apart from the plurality of threads vertically hung down; and a plurality of movable arms being respectively movable in the chamber from a first position horizontally apart from the plurality of threads vertically hung down, via a second position in contact with any of the plurality of threads, to a third position to make the threads in contact be in contact with corresponding winding bobbins.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of PCT InternationalApplication No. PCT/JP2019/049506 (filed Dec. 18, 2019), which is inturn based upon and claims the benefit of priority from Japanese PatentApplication No. 2019-062713 (filed Mar. 28, 2019), the entire contentsof which are incorporated herein by reference.

BACKGROUND Technical Field

The disclosure herein relates to a vacuum processing device availablefor a process of forming a coating on a reinforcement fiber, and inparticular relates to a vacuum processing device in which a bobbin canbe exchanged while the most part of the device is kept evacuated.

Description of the Related Art

Ceramic matrix composites (CMC) are articles in which reinforcementfibers of ceramics are combined by matrices of ceramics. The SiC/SiCcomposite for example, in which reinforcement fibers of silicon carbideare combined by a matrix of silicon carbide, shows promise for theapplication as turbine components or such of jet engines.

A coating such as that of boron nitride is sometimes applied to siliconcarbide fibers in order to strengthen binding force to its matrices. Avacuum processing is applicable to formation of the coating although itis no more than an example. A reaction chamber is often required to bevery long so as to assure sufficient residence time therein in light ofan enough reaction time, and accordingly a vacuum pump must be kept torun for a considerably long time in order to get a sufficient degree ofvacuum throughout the chamber.

On the other hand, the reaction chamber must be exposed to theatmosphere before and after the processing so that a series ofoperations to load new fibers into the chamber, make them pass throughthe reaction chamber, and connect them to winding bobbins. The interiorof the reaction chamber after being exposed to the atmosphere wouldabsorb gas molecules and thus a very long time might be necessary toreach a sufficient degree of vacuum again.

Therefore treatments before and after the processing must require a verylong time (all night and all day for example), even though theprocessing by itself might only require a comparatively short time. Sucha vacuum processing consequently has a limited productivity. If the timefor exposing the interior of the coating device to the atmosphere couldbe shortened, the productivity could be prominently improved.

Some arts have been proposed to enable execution of operation ofconnecting fibers to winding bobbins under vacuum, thereby enablingexchange of bobbins without exposing reaction chambers to theatmosphere. Related arts are disclosed in Japanese Patent ApplicationLaid-open No. H07-197264, Japanese Patent Application Laid-open No.2011-157632, and Japanese Patent Application Laid-open No. 2015-203129.

SUMMARY

Simultaneous vacuum processing on a plurality of threads ofreinforcement fibers would, if possible, further improve productivityprominently. Under vacuum, more specifically in a circumstance where anymanual process is unavailable, it is uneasy to pass reinforcement fibersthrough such an elongated reaction chamber and successfully deliver themto a winding bobbin beyond the chamber. To simultaneously handle aplurality of threads of reinforcement fibers is, as a matter of course,more difficult. While reinforcement fibers would be readily fuzzed, suchfuzz frequently touches many sites on the interior of the device or fuzzon other reinforcement fibers to change trajectories of thereinforcement fibers. This further complicates simultaneous handling ofa plurality of reinforcement fibers. The device described below has beencreated in view of these problems.

According to an aspect, a device of executing vacuum processing on aplurality of threads of reinforcement fibers is provided with: a chamberincluding a single main chamber executing the vacuum processing andbeing capable of keeping the chamber as a whole in a depressurizedstate; a plurality of feeding rollers so arranged as to hang down theplurality of threads in the main chamber with keeping the threads fromeach other; a plurality of winding bobbins respectively winding theplurality of threads independently, the winding bobbins arranged in thechamber horizontally apart from the plurality of threads vertically hungdown; and a plurality of movable arms being respectively movable in thechamber from a first position horizontally apart from the plurality ofthreads vertically hung down, via a second position in contact with anyof the plurality of threads, to a third position to make the threads incontact be in contact with corresponding winding bobbins.

Advantageous Effects

It is enabled to guide a plurality of fibers to a plurality of bobbinsand start winding them with keeping a device as a whole in adepressurized state.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic sectional view of a vacuum processing device inaccordance with an embodiment.

FIG. 2 is a perspective view of the device particularly showing arelation of a set of a movable arm and a winding bobbin.

FIG. 3 is a plan view of a set of a movable arm and a pulley

FIG. 4 is a plan view showing a relation between plural threads ofreinforcement fibers and trajectories of movable arms.

DESCRIPTION OF EMBODIMENTS

Exemplary embodiments will be described hereinafter with reference tothe appended drawings. It is particularly noted that these drawings arenot always drawn to scale exactly and therefore dimensional relationsamong elements are not limited to those shown therein.

Referring to FIG. 1, a vacuum processing device 1 of the presentembodiment is available for use in formation of a coating onreinforcement fibers F by a process that uses vacuum, such as CVD or PVDfor example. Examples of the reinforcement fibers are those of siliconcarbide, graphite or alumina and examples of the coating are those ofboron nitride or carbon but these examples are not exhaustive andlimiting. The present embodiment could be used for vacuum processing ona single fiber or a yarn, a tow, a band or a fabrics in which aplurality of fibers are bundled, or yet a plurality of threads thereof.

The vacuum processing device 1 is generally composed of a chamber 3, oneor more feeding bobbins 5 for feeding reinforcement fibers F, feedingrollers 7 for respectively hanging down one or more threads ofreinforcement fibers F fed therefrom, a processing device 9 forexecuting processing such as CVD, one or more sets of movable arms 11and pulleys 23 which respectively guide one or more threads ofreinforcement fibers CF after passing through the processor 9, and oneor more winding bobbins 13 for respectively winding up the one or moreguided threads of reinforcement fibers CF. Although details will bedescribed later, by the plural sets of the feeding bobbins 5, thefeeding rollers 7, the pulleys 23 and the winding bobbins 13, the pluralthreads of the reinforcement fibers F are made to pass through thesingle processor 9 simultaneously and in parallel, thereby executingvacuum processing.

The chamber 3 is a vacuum chamber that can keep itself as a whole in adepressurized state. The chamber 3 is further sectioned into a pluralityof sub-chambers. In the example shown in the drawing, the chamber 3 iscomprised of a first sub-chamber 3 a housing the feeding bobbins 5 andthe feeding rollers 7, a single main chamber 3 b housing the processor9, and a second sub-chamber 3 c housing the movable arms 11 and thewinding bobbins 13 and such, and these chambers are in communicationwith each other. The chamber 3 may have other sub-chambers if necessary.

One or more vacuum pumps not shown are connected to the chamber 3 inorder to set the interior of the chamber 3 in a depressurized state.Although the vacuum pumps are connected at least to the firstsub-chamber 3 a, independent vacuum pumps may be further connected tothe main chamber 3 b and the second sub-chamber 3 c, respectively.Additional vacuum pumps may be connected to additional sub-chambers ifthey exist.

The first sub-chamber 3 a, the main chamber 3 b and the secondsub-chamber 3 c take a form of being piled up vertically in order tohang the reinforcement fibers F vertically down and pass them throughthe processor 9. Further the main chamber 3 b may be verticallyelongated in order to ensure a sufficient reaction time in the processor9. Therefore these elements may take a form in that the secondsub-chamber 3 c is installed on a first floor in a building, the mainchamber 3 b on a second floor, and the first sub-chamber 3 a on anystill upper floor, for example.

At least in between the first sub-chamber 3 a and the main chamber 3 band in between the main chamber 3 b and the second sub-chamber 3 c,gates 15, 17 for gas-tightly separating them may be interposed. To thegate 15, 17 applicable are gate-valves but still applicable are anyother types of valves, such as pendulum valves or butterfly valves.Preferably actuators such as hydraulic cylinders are respectivelyconnected thereto for driving the gates 15, 17.

Between the first sub-chamber 3 a and the main chamber 3 b and betweenthe main chamber 3 b and the second sub-chamber 3 c, gas-tightcommunication may be established through communication pathsrespectively. The gates 15, 17 may be provided in these communicationpaths.

The feeding bobbins 5 are housed in the first sub-chamber 3 a andactuators such as motors are respectively connected thereto for theserotation. When closing the gate 15, as the first sub-chamber 3 a isgas-tightly separated from the main chamber 3 b, the first sub-chamber 3a is allowed to be exposed to the atmosphere with keeping the mainchamber 3 b evacuated, thereby allowing carry-in or exchange of thefeeding bobbins 5.

In the first sub-chamber 3 a, still another device such as tensiondetectors 19 may be installed. The tension detectors 19 are used for thepurpose of detecting tension acting on the reinforcement fibers F beingfed out.

The reinforcement fiber F are respectively wound around the feedingbobbins 5 and are in this state carried therein to serve as a subjectfor the vacuum processing. Preferably as shown in FIG. 2, a weight W iscombined with a leading end of each of the reinforcement fibers F. Theweight W by gravity guides the reinforcement fiber F through theprocessor 9 to a space between a corresponding movable arm 11 and acorresponding pulley 23.

Referring again to FIG. 1, the feeding rollers 7 are also housed in thefirst sub-chamber 3 a and are, maybe not clearly shown therein, arrangedhorizontally apart from each other. The horizontal arrangement of themis special to the combination of the corresponding movable arms 11 andthe corresponding pulleys 23. More specifically, the feeding rollers 7are so disposed that, as the reinforcement fibers F fed out of thefeeding bobbins 5 pass through the feeding rollers 7 and are there hungdown vertically, the reinforcement fibers F pass through the processor 9and respectively reach the spaces between the corresponding movable arms11 and the corresponding pulleys 23. As will be understood from FIG. 4as a plan view although maybe not clearly shown in FIG. 1 as a schematicplan view, the plurality of combinations of feeding rollers 7, movablearms 11 and pulleys 23 are so arranged as to keep the plurality ofthreads of reinforcement fibers F to be parallel but apart from eachother in the processor 9. As to this arrangement, more detaileddescriptions will be given later. The feeding rollers 7 may be fixed tothe first sub-chamber 3 a or may be made movable to regulate thesepositions.

Referring again to FIG. 1, the processor 9 is housed in the main chamber3 b and has a constitution adapted for executing a vacuum processingsuch as CVD or PVD. In a case where a coating of boron nitride is to beformed for example, the processor 9 can contain tubing for introducingboron fluoride gas, ammonia gas and nitrogen gas as a carrier and aheating furnace. The constitution of the processor 9 has many variationsof course and is properly selected therefrom depending on an intendedprocessing. The reinforcement fibers F hung down from the feedingrollers 7 vertically pass through the processor 9 and are therebysubject to a processing such as coating. The processor 9, in particularthe heating furnace thereof, may be formed in a cylindrical shape, or ina polygonal column similar to a cylinder. As the plurality of threads ofreinforcement fibers F passes its center or its vicinity, uniformprocessing on the respective threads is enabled.

Referring to FIG. 2 in combination with FIG. 1, a set of the movable arm11 and the pulley 23 is so arranged in the second sub-chamber 3 c as tobe horizontally apart from the reinforcement fiber CF drawn by gravityand naturally falling vertically down, and also as to put thereinforcement fiber CF in therebetween. More specifically, the leadingend of the reinforcement fiber CF can reach the space between thecorresponding movable arm 11 and the corresponding pulley 23 generallyonly by action of gravity without any other means.

Referring further to FIG. 3 in combination with FIG. 2, the movable arm11 is vertically below the pulley 23 and is, in a stand-by state,disposed to be also apart horizontally from the pulley 23. The movablearm 11 is, as illustrated by the two-dotted chain line L in FIG. 3,linearly movable forward and rearward, and an indent of the pulley 23is, in planar view, aligned with the line L. More specifically, themovable arm 11 standing by at an initial position where it staysrearward, when moving forward, gets in contact with the reinforcementfiber CF, and, when moving further forward, guides the reinforcementfiber CF to the pulley 23 and rests it in the indent thereof.

Each movable arm 11 may be, at its leading end, provided with a capturedevice in order to capture and guide the reinforcement fiber CF to itscenter. One example of the capture device is, as best shown in FIG. 3, apair of guide plates 25 that spread in a V-letter shape in planar view.Each pulley 23 may be similarly provided with a capture device such as apair of guide plates 27. They are beneficial in surely capturing thereinforcement fiber CF even if its trajectory is considerably changed.In place of or in addition to the guide plates applicable is, of course,any structure in any other shape, induction means such as a magnet forinducing a weight W, an electrically charged body for electrostaticallyinducing the reinforcement fiber CF, or an adhesive agent or aviscoelastic body to which fibers adhere.

The movable arm 11 is movable from an initial stand-by position shown bythe solid line in FIG. 2, via a second position in contact with thereinforcement fiber CF as described above, at least further to a thirdposition shown by the two-dotted chain line in FIG. 2. On the otherhand, the winding bobbin 13 is arranged to be horizontally apart fromthe reinforcement fiber CF vertically hung down and, in planar view,overlap with the leading end of the movable arm 11 advanced to the thirdpositon. When the movable arm 11 is at the third position, if thereinforcement fiber CF is lowered down along with the weight W, or thewinding bobbin 13 is raised up, the reinforcement fiber CF gets incontact with the winding bobbin 13. Any structure such as a funnel maybe provided just above the winding bobbin 13 in order to guide theweight W to the winding bobbin 13.

Travel of the movable arms 11 may be horizontal and linear, and a linearmotion mechanism is available for such action. More specifically, thevacuum processing device 1 may be provided with a linear motionmechanism as a mechanism for driving the movable arms 11. An example ofthe linear motion mechanism is, as best shown in FIG. 1, arack-and-pinion mechanism. For example, the movable arms 11 may beprovided with racks and the vacuum processing device 1 may be providedwith pinions 21 in mesh with these racks. As the pinions 21 can bedriven by revolving motion, the linear motion mechanism can be drivenfrom the exterior of the sub-chamber 3 c by a structure, for example, inthat a motor is installed at the exterior of the sub-chamber 3 c andgas-tightly sealed shafts penetrating the sub-chamber 3 c transmits itsmotion to the internal mechanism. As the driver such as the motor thatwould contaminate the internal atmosphere can be outside the chamber 3,this structure is beneficial in executing high-purity vacuum processing.

Of course, instead of the rack-and-pinion mechanism, any other linearmotion mechanism such as a ball screw, a linear motor, a hydraulicdevice or such is available.

Linear motion mechanisms may be respectively given to the movable arms11, whereas the plurality of movable arms 11 may be combined together asshown in FIG. 1 and a single linear motion mechanism may be given tothis combination. The latter structure could not drive the movable arms11 independently but is beneficial in reducing the number of elementsthat cause contamination of the atmosphere.

As will be understood from the above description, each winding bobbin 13is so arranged at a position where it can take up the reinforcementfiber CF when the movable arm 11 moves to the third position. While anydriving device such as a motor is coupled thereto for its rotation, itcan be placed at the exterior of the sub-chamber 3 c as a gas-tightlysealed shaft can intermediate the power input. The winding bobbin 13 asbeing given rotation in advance or in synchronous with the travel of themovable arm 11 takes up and winds up the reinforcement fiber CF. Thenthe weight W may be separated by using a cutter or the reinforcementfiber CF along with the weight W can be wound up. Further a tray H maybe placed below the winding bobbin 13 in order to receive the weight Wthere.

Of the reinforcement fiber F that is vertically drawn, the upper end issupported by the roller 7 and the lower end is supported by the pulley23. Thus this combination puts the reinforcement fiber F accurately inplace in the processor 9. The sets each consisting of the feeding bobbin5, the feeding roller 7, the pulley 23 and the winding bobbin 13 may beas shown in FIG. 1 arranged to be vertically apart from each other.These sets are further arranged to be horizontally apart from eachother, thereby enabling an arrangement in which the reinforcement fibersCF are as illustrated in FIG. 3 arranged to be apart from each other. Ina case where the reactor tube wall 3 f of the processor 9 is for examplecylindrical, the reinforcement fibers CF can be arranged at evenintervals around a circle coaxial to the cylinder. Further areinforcement fiber CF may be additionally arranged at the center of thecylinder and further at even distances to the others. Arrangement ateven intervals is beneficial in equalizing the vacuum processing on therespective reinforcement fibers CF.

By properly arranging the trajectories L of the movable arms 11depending on the horizontal arrangement of the reinforcement fibers CF,interference among the fibers CF and respective structures of the devicecan be avoided. For example, the reinforcement fibers CF may be arrangedat vertexes and a center of a regular hexagon as shown in FIG. 4. Foursets of the movable arms 11 and the pulleys 23 may be then so arrangedas to make the trajectories L of the movable arms 11 parallel with eachother and as to be apart from each other in directions distinct from thetrajectories L. The remaining three sets may be so arranged as to besimilarly apart from each other and make these trajectories L obliquelyintersect with the formers. An arrangement such as this prevents themovable arms 11 from interfering with each other if they make linearmotions. This is beneficial in handling a plurality of threads ofreinforcement fibers F simultaneously. Of course arrangements of themovable arms 11 and the pulleys 23 are not limited thereto and thenumber of sets thereof is not limited to seven but can be more or less.

By closing the gate 17, the main chamber 3 b and the second sub-chamber3 c are gas-tightly cut off from each other. Thus the second sub-chamber3 c could be exposed to the atmospheric air with keeping the mainchamber 3 b evacuated, thereby enabling carry-in and exchange of thewinding bobbins 13. The reinforcement fibers CF being processed aretaken out in a state where they are wound around the winding bobbins 13.

According to the present embodiment, steps for vacuum processing by CVDor PVD on reinforcement fibers are for example those described below.

Referring to FIG. 1, the interior of the chamber 3 is kept in adepressurized state by vacuum pumps not shown therein. By closing thegates 15, 17, the first and second sub-chambers 3 a, 3 c are gas-tightlycut off from the main chamber 3 b. The outside air is next introducedinto the first and second sub-chambers 3 a, 3 c so that these chambersare exposed to the atmospheric air. The main chamber 3 b is even thenkept in the depressurized state.

To the first sub-chamber 3 a exposed to the atmospheric air, feedingbobbins 5 with reinforcement fibers F wound therearound are respectivelyintroduced. If vacant feeding bobbins 5 are already installed in thefirst sub-chamber 3 a, they are replaced with the formers. Thereinforcement fibers F are respectively drawn from the introducedfeeding bobbins 5, and made to pass through the tension detectors 19 ifinstalled, and are made to respectively pass through the feeding rollers7 and hung down therefrom vertically. To the respective leading ends,the weights W are respectively combined.

In parallel, to the second sub-chamber 3 c exposed to the atmosphericair, vacant winding bobbins 13 are respectively introduced. If windingbobbins 13 with already processed reinforcement fibers CF woundtherearound are installed therein, they are replaced with the formers.

The first and second sub-chambers 3 a, 3 c are closed and its interioris evacuated by the vacuum pumps not shown in the drawing. When asufficient degree of vacuum is obtained, the gates 15, 17 are opened andthereby the first sub-chamber 3 a, the main chamber 3 b and the secondsub-chamber 3 c are mutually in communication. Then, as shown in FIG. 2,the movable arms 11 respectively stand by at the retracted positions.

The plurality of threads of reinforcement fibers F vertically hung downfrom the feeding rollers 7 passes through the processor 9 disposed inthe main chamber 3 b. The reinforcement fibers F passing through theprocessor 9 further fall down vertically and each leading end thereofrespectively reaches a space between a corresponding movable arm 11 anda corresponding pulley 23. The respective movable arms 11 are movedforward to respectively get in contact with the threads and place theminto the indents of the pulleys 23.

The respective movable arms 11 are further moved forward to render therespective threads in contact with the corresponding winding bobbins 13and the reinforcement fibers CF are respectively wound up by the windingbobbins 13. In parallel, the movable arms 11 are moved rearward.

The processor 9 is put into operation so as to execute processing suchas coating on the reinforcement fibers F and simultaneously the windingbobbins 13 are started rotating to wind up the processed reinforcementfibers CF at a steady speed.

As will be understood from the above description, when the vacuumprocessing is finished and then the bobbins needs to be replaced, thefirst and second sub-chambers need to be exposed to the atmospheric airwhereas the main chamber can be kept evacuated. As the main chamberhaving the largest capacity and the broadest inner area among any partsof the vacuum processing device is kept evacuated, only a short time isneeded to obtain a required degree of vacuum after replacing thebobbins. Therefore the vacuum processing can be repeatedly executed withachieving high productivity.

Further according to the present embodiment, the work for connecting thefibers to the bobbins can be carried out under vacuum. Still furtheraccording to the present embodiment, a plurality of threads of fiberscan be in parallel served for vacuum processing.

In the atmospheric air, if any, the aforementioned work can be manuallycarried out readily. Or any air nozzle could be used to suck fibersalong with the air and then put them in position. More specifically, inthe atmospheric air, if any, the work could be automated. The work,however, needs to be carried out in a state where the fibers run throughthe main chamber and necessarily the main chamber is required to beexposed to the atmospheric air. This is, as reiterated heretofore,extremely damaging to productivity. The manual operation and the nozzlesucking are both impracticable under an evacuated condition.

According to the present embodiment, as the reinforcement fibers arecaptured and guided to the winding bobbins by the movable arms, the workis automatically executable even under an evacuated condition.Necessarily the main chamber is not required to be exposed to theatmospheric air and thus high productivity is obtained. Further, byproperly arranging the respective elements of the device, a plurality ofthreads can be simultaneously handled. Higher productivity can besought.

Although certain embodiments have been described above, modificationsand variations of the embodiments described above will occur to thoseskilled in the art, in light of the above teachings.

INDUSTRIAL APPLICABILITY

A vacuum processing device that enables guiding a plurality of fibers toa plurality of bobbins and starting winding them with keeping a deviceas a whole in a depressurized state is provided.

What is claimed is:
 1. A device of executing vacuum processing on aplurality of threads of reinforcement fibers, comprising: a chamberincluding a single main chamber executing the vacuum processing andbeing capable of keeping the chamber as a whole in a depressurizedstate; a plurality of feeding rollers so arranged as to hang down theplurality of threads in the main chamber with keeping the threads fromeach other; a plurality of winding bobbins respectively winding theplurality of threads independently, the winding bobbins arranged in thechamber horizontally apart from the plurality of threads vertically hungdown; and a plurality of movable arms being respectively movable in thechamber from a first position horizontally apart from the plurality ofthreads vertically hung down, via a second position in contact with anyof the plurality of threads, to a third position to make the threads incontact be in contact with corresponding winding bobbins.
 2. The deviceof claim 1, wherein travel from the first position via the secondposition to the third position is guided in a horizontal first directionand the movable arms are disposed apart from each other in a horizontalsecond direction distinct from the first direction.
 3. The device ofclaim 2, further comprising: a linear motion mechanism driving therespective movable arms linearly in the first direction.
 4. The deviceof claim 3, wherein the linear motion mechanism comprises a rack and apinion in mesh with the rack, and the pinion is rotated from an exteriorof the chamber.
 5. The device of claim 1, wherein each of the movablearms comprises a leading end having a guiding plate for capturing thethread in contact with the movable arm and guiding to a center.
 6. Thedevice of claim 1, wherein the chamber includes a first sub-chamberhousing the feeding rollers, and a second sub-chamber housing thewinding bobbins and the movable arms, and the main chamber is configuredto temporarily get gas-tightly separated from the first sub-chamber andthe second sub-chamber.